4 large starchy potatoes, peeled and cut into chunks
4 medium parsnips, peeled and chopped into chunks
1 small peeled onion
1 box frozen chopped organic spinach, defrosted and squeezed dry
2 tablespoons butter
About 1/2 cup milk, divided
1/2 cup heavy cream
Freshly ground black pepper
Freshly grated nutmeg
2 eggs, beaten
1 cup Gruyère cheese, grated or grated parmesan cheese
For the roasted mushrooms:
2 1/2 pounds mixed mushrooms - when you bring them home, wipe them, stem them and slice them (portobellos should be gilled and sliced, buttons may be halved, shitakes, oysters or other wild mushrooms may be coarsely chopped)
8-10 cloves garlic, crushed
Several sprigs fresh thyme
1/2 cup extra virgin olive oil (EVOO)
Put the potatoes and parsnips in large pot and cover with water. Bring the water to a boil, over medium heat. Salt the water and cook the vegetables until tender, 12-15 minutes. Drain and return them to the hot pot. Grate in 3-4 tablespoons of onion, then add the spinach, butter, half of the milk and all of the cream. Season with salt, pepper and a little freshly grated nutmeg, to taste. Mash the mixture together and taste to adjust the seasonings. Add the extra splash of milk if the potatoes are too tight. Cool to room temperature, then stir in the eggs and transfer the mixture to a casserole dish. Cover with cheese and sprinkle with paprika. Cool and chill for a make-ahead meal.
Pre-heat the oven to 400°F.
Place the casserole on a baking sheet and put it in the lower third of the oven. Bake until hot and golden, about 35-40 minutes.
In a medium size baking dish, toss the mushrooms with the garlic, thyme and EVOO. Roast until dark and tender, about 30 minutes. Stir in the lemon juice and season with salt and pepper, to taste. Serve the mushrooms alongside the casserole.